This proposal seeks matching funds to construct new laboratories suitable to house the research, research training, and research support activities of the recently established Molecular Genetics Center for Pediatric Diseases of the Children's Research Institute (CRI), in a consolidated physical location within the Children's National Medical Center (CNMC). THE Center will house seven principal investigators all focused on gene discovery, molecular diagnosis, and gene therapy, five of whom have been recruited since July 1998, and receive $2.2 million/year in direct costs from externally funded research grants. Dr. Eric Hoffman, Director of the Molecular Genetics Center, will provide the scientific leadership, together with additional oversight by Dr. Mark Batshaw, Chief Academic Officer of CNMC and Director of CRI, and Dr. Stephan Ladisch, Scientific Director of CRI. The Center will occupy 7,286 square feet of net new laboratory construction on the 6th floor, and will include state-of- the-art research laboratories, work stations, offices, and meeting rooms (total of 11,268 square feet). Together with 2,000 square feet of recently completed space on the 5th floor of CRI, this space will house the 40 researchers of the Center, including graduate students from the multi- institution Institute for Biomedical Sciences and clinician scientists in the research training curriculum at CNMC. The Center will include four core facilities (automated sequencing, microarray, HPLC/mass spectrometry, and tissue culture) for use by all Center investigators and other research faculty. The proposed facility will provide space, currently lacking, that will be suitable for the recently established research activities in molecular genetics at CNMC.